Wings of civil aircraft are often equipped with a plurality of different control surfaces, which are movably supported on the wing. During flight, the control surfaces are exposed to an airflow and, depending on their orientation to the wing and thus to the airflow surrounding the wing, produce a force with a certain magnitude and direction.
For example, control surfaces serve for increasing the surface area and camber of the wing in order to increase the lift coefficient are widespread and enable a reduction of required flow velocities particularly for facilitating take-off and landing. These “high-lift” surfaces are often arranged on further inboard regions and central regions of the wing. They may exemplarily be realized in the form of leading edge slats and/or trailing-edge flaps, which may be moved between a retracted position, in which they constitute a part of a clean wing, and an extended position, in which they may provide an enlarged surface area as well as a gap to a main wing structure.
Different support and guiding devices are known for moving the trailing edge flap between the retracted and extended positions. A possible mechanism for guiding a high-lift flap relative to a trailing edge region of a wing is the so-called “dropped hinge”, in which the flap rotates around a fixed hinge line at a distance to the flap. A common layout includes an inboard flap having two flap supports and one outboard flap having two flap supports. The outboard flap usually has a tapered form, i.e. the profile depth decreases in an outboard direction. The rotation of the flap around the above-mentioned hinge line is adapted to the tapered form of the flap, such that the inboard support of the outboard flap conducts a cyclic rotation with a larger diameter than the outboard support. This leads to a motion of the flap on a conical surface section with a virtual tip of the conus outboard of the wing tip.
As an example, patent document WO 2012 045 796 A1 shows a high-lift system for a wing of an aircraft, comprising movably held high-lift flaps, at least one drive unit, at least one transmission shaft connected to the drive unit, and several actuator devices, distributed on the transmission shaft and connected to the high-lift flaps, for moving the high-lift flaps.